[src/trunk]: src/sys/arch/mips/mips keep V0 value (system call number) and re...

[shin <shin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/0aa2b039c2ea
branches:  trunk
changeset: 503723:0aa2b039c2ea
user:      shin <shin%NetBSD.org@localhost>
date:      Mon Feb 12 10:32:14 2001 +0000

description:
keep V0 value (system call number) and restore it in exception frame,
when error is ERESTART. otherwise, user process will re-issue syscall
with broken system call number and get SIGSYS signal and terminate.

patch made by Jason R Thorpe <thorpej%zembu.com@localhost>. tested by me.

diffstat:

 sys/arch/mips/mips/syscall.c |  14 ++++++++------
 1 files changed, 8 insertions(+), 6 deletions(-)

diffs (70 lines):

diff -r b237c9635cd4 -r 0aa2b039c2ea sys/arch/mips/mips/syscall.c
--- a/sys/arch/mips/mips/syscall.c      Mon Feb 12 09:28:40 2001 +0000
+++ b/sys/arch/mips/mips/syscall.c      Mon Feb 12 10:32:14 2001 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: syscall.c,v 1.2 2001/01/18 17:48:01 tv Exp $   */
+/*     $NetBSD: syscall.c,v 1.3 2001/02/12 10:32:14 shin Exp $ */
 
 /*-
  * Copyright (c) 2001 The NetBSD Foundation, Inc.
@@ -80,7 +80,7 @@
 
 #include <sys/cdefs.h>                 /* RCS ID & Copyright macro defns */
 
-__KERNEL_RCSID(0, "$NetBSD: syscall.c,v 1.2 2001/01/18 17:48:01 tv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: syscall.c,v 1.3 2001/02/12 10:32:14 shin Exp $");
 
 #include "opt_ktrace.h"
 #include "opt_syscall_debug.h"
@@ -138,7 +138,7 @@
 syscall_plain(struct proc *p, u_int status, u_int cause, u_int opc)
 {
        struct frame *frame = (struct frame *)p->p_md.md_regs;
-       mips_reg_t *args, copyargs[8];
+       mips_reg_t *args, copyargs[8], ov0;
        size_t code, numsys, nsaved, nargs;
        const struct sysent *callp;
        int error;
@@ -152,7 +152,7 @@
 
        callp = p->p_emul->e_sysent;
        numsys = p->p_emul->e_nsysent;
-       code = frame->f_regs[V0];
+       ov0 = code = frame->f_regs[V0];
 
        switch (code) {
        case SYS_syscall:
@@ -233,6 +233,7 @@
                frame->f_regs[A3] = 0;
                break;
        case ERESTART:
+               frame->f_regs[V0] = ov0;        /* restore syscall code */
                frame->f_regs[PC] = opc;
                break;
        case EJUSTRETURN:
@@ -255,7 +256,7 @@
 syscall_fancy(struct proc *p, u_int status, u_int cause, u_int opc)
 {
        struct frame *frame = (struct frame *)p->p_md.md_regs;
-       mips_reg_t *args, copyargs[8];
+       mips_reg_t *args, copyargs[8], ov0;
        size_t code, numsys, nsaved, nargs;
        const struct sysent *callp;
        int error;
@@ -269,7 +270,7 @@
 
        callp = p->p_emul->e_sysent;
        numsys = p->p_emul->e_nsysent;
-       code = frame->f_regs[V0];
+       ov0 = code = frame->f_regs[V0];
 
        switch (code) {
        case SYS_syscall:
@@ -357,6 +358,7 @@
                frame->f_regs[A3] = 0;
                break;
        case ERESTART:
+               frame->f_regs[V0] = ov0;        /* restore syscall code */
                frame->f_regs[PC] = opc;
                break;
        case EJUSTRETURN: